1. Field of Invention
This invention pertains to a device for exchanging optical signals between a stationary and a moving object, and more particularly for exchanging signal with a rotary member such as shaft.
2. Description of the Prior Art
Most industrial and power plants include rotary equipment which is subjected to large loads. Because the rotary equipment is a crucial element in these plants, it is desirable to monitor it so that potential failures due to temperature, strain and stress can be sensed before a catastrophic breakdown of the equipment occurs. Traditionally electro-mechanical and electronic sensors were utilized to this purpose which were mounted on the rotary equipment and coupled to stationary detection equipment through mechanical slip rings, or some electronic means.
Recently sensors have been developed which can detect high temperature, strain or stress levels using optical fibers and related devices. However these devices could not be installed on rotating equipment for a lack of a suitable interface.